Portable X-ray inspection systems for trucks are generally known. Such systems are typically used to perform non-invasive inspection of trucks for contraband (e.g., explosives, drugs, etc.). Often an X-ray beam is directed through the truck to a set of detectors on an opposing side.
As the radiation of the X-ray beam passes through the truck, the contents of the truck attenuate the beam based upon the density of the contents. Based upon the attenuation, an image may be formed of the truck's contents. By comparing a truck's manifest with the X-ray image, law-enforcement personnel may make a determination of whether on not they have probable cause to believe that any laws have been broken.
While conventional X-ray system are effective in most situations, higher power X-ray systems are needed in some other situations. For example, a tanker full of fuel or a rail car loaded with an industrial chemical would require a relatively high power X-ray beam to penetrate the vehicle to be inspected.
The use of high power X-rays requires an increased level of shielding. However, shielding is heavy and does not significantly contribute to the overall effectiveness of the imaging system. On the other hand, without adequate shielding, people working adjacent a vehicle being inspected would suffer radiation exposure, injury and even death. Because of the importance of cargo inspection for contraband, a need exists for a more effective method of protecting personnel from X-rays during the imaging of vehicles.